Inactivity is greatest heart risk factor for women over 30: study

NEW YORK (Reuters Health) - Heart disease is the single
biggest killer of women and inactivity is the biggest
contributor to heart disease for all but the youngest ones,
according to Australian researchers.

They parsed the sources of cardiovascular risk among women
of all ages in Australia and found smoking, obesity and high
blood pressure are near the top of the list. But if all
sedentary women ramped up their activity levels, the largest
number of deaths would be averted.

"Understanding the risks associated with the development of
serious health problems can inform more targeted intervention
strategies," said the study's lead author Wendy Brown, an
exercise physiologist at the University of Queensland.

Heart disease is the leading killer of women in the United
States, where an estimated one in four women dies of the
disease, and similar statistics prevail in Australia.

To measure the importance of various risk factors for heart
disease, Brown and her team analyzed data from a long-term study
that followed Australian women from 1996 to 2011, surveying them
about their lifestyle and health every three years.

The roughly 30,000 participants ranged from 22 to 90 years
old and fell into three groups born from 1973 to 1978, 1946 to
1951 and 1921 to 1926.

The researchers calculated for each group the extent to
which the presence of heart disease could be attributed to body
mass index (BMI, a measure of weight relative to height),
physical inactivity, high blood pressure or smoking.

Overall, being sedentary was the greatest contributor to
heart disease among women over age 30, including women as old as
90.

Smoking was the biggest culprit among women between the ages
of 22 and 27. In that group, where heart disease is rare,
smoking accounted for about 60 percent of it, according to the
results published in the British Journal of Sports Medicine.

High blood pressure was least common among the youngest
women, and high BMI (overweight or obese) was most common in the
middle age group.

Inactivity was widespread, with 65 percent of women 73 to 78
years old and 81 percent of those 85 to 90 getting little or no
physical activity.

Based on rates of death from heart disease in Australia, the
researchers calculated that if all the women represented by the
study population could do about 1 hour of moderately intense
activity a day, some 2,612 deaths would be avoided.

That's more Australian women than are killed in road
accidents each year, they point out.

"Physical activity hasn't been studied as well; the other
risk factors (like body mass index) have been more targeted in
the past," said Nisha Parikh, a cardiologist at the University
of California, San Francisco, who was not involved in the study.

"The nice thing is all these things track together," Parikh
told Reuters Health. "If you increase your physical activity,
you generally lower body mass index, and you're also going to
have an impact on lowering blood pressure," she said.

The study shows the importance of boosting activity levels
at all ages, she added, and although that can be difficult,
there are many simple ways for busy people to get in a few extra
steps each day, like taking the stairs and parking a little
farther away from their destination.

"Those kinds of things increase physical activity in a way
that doesn't impact the rest of the things busy people have
going on," Parikh said.